Osborn p



(Nn Model.)

0. P. LOOMIS.

GOMMUTATOR BRUSH FOR ELECTRIC GENERATORS. No. 381,394.

Patented Apr. 17, 1888.

' 5381 m flttoz-nua% L/ v UNITED STATES PATENT OFFICE.

OSBORN P; LOOMIS, OF SOMERVILLE, MASSACHUSETTS, ASSIGNOR TO THE LOOMISELECTRIC MANUFACTURING COMPANY, OF NEW YORK,'N. Y.

COMMUTATOR-BRUSH FOR ELECTRIC GENERATORS.

SPECIFICATION forming part of Letters Patent No. 381,394, dated April17, 1888.

Application filed December 15, 1856 Serial No. 2:21.649. (No model.)

To all whom it may concern:

Beit known that I, OSBORN P. Looms, a citizen of theUnitedStates,residing atSomerville, in the county of Middlesex and State ofMassachusetts, have invented certain new and useful Improvements in Commutator-Brushes for Magnetic Electric Machines, of which the fol lowingis such a full, clear, and exact description as will enable any oneskilled in the art to which it appertains to make and use the same,reference being had to the accompanying drawings, forming part of thisspecification.

The object of my invention is .to secure as great convenience aspossible in the manipulation and manufacture of the collectingbrushesfor dynamos or other magneto-electrio machines.

The invention consists in a collecting-brush composed of sheet metalstrips, which has metal pieces at one end,to which the strips aresoldered, and hearing at itsother end upon the commutator, the stripsbeing arranged di agonally to the plane of the brush.

Figure 1 represents a plan View of my new collecting brush; Fig. 2, aside elevation, partly sectioned, of my brush and a holder; and Fig. 3,an end view of the devices illus trated in Fig. 2.

The same letters of reference indicate the same parts throughout thethree figures of the drawings.

The commutator-brush I make of sheet-copper strips G, which are held atone end between triangular shaped brass pieces L and M, to which thestrips are soldered. The strips are diagonally arranged, as showninFigs. 1 and 3, so that the planeof the strips,when the brush is heldin a horizontal position, makes an angle of from forty degrees to sixtydegrees with the horizon-that is to say, I lay them edgewise, but notvertically or horizontally,so that an increased bearing is secured uponthe commutator,the said bearing being the resultant of the end,a portionof the length,and the diagonal arrangement. This not only gives me anincrease of bearing or contact over the strips when verticallyarranged,but it also, by reason of the diagonal arrangenient,makes thebrush as flexible as the old form, wherein the strips are superimposedupon one another horizonlally, which latter arrangement isobjectionable, for the reason't-hat the strips, when so arranged,are notsubjected to the same wear, the lower one being first to wear away andfall away from the commutator or upon a strip of the commutator remotefrom the one upon which the brush bears, thus causing sparking and ashort'circuiting of the current. In the arrangement I have justdescribed the flexibility of the brush is not interfered with, and ithas all the advantages of the costly wire brush so much used, and is farsuperior to manufacture and to manipulate. A vertical arrangement mightsometimes be found advantageous in certain cases; but I prefer thediagonal arrangement spoken of.

Of course I do not wish to limit myself to any angle at which the samemay be arranged, and only mention the above angles as defining a limitto the angle; but of course this may be varied below or above this limitwithout departing from my invention.

The clampFofthe brush-holder is carried forward froma stud, A,projecting from the machine toward the commutator H. This clamp is,provided with a rectangular opening for receiving the brush L G M, andis adapted to be clamped in place by an adjusting-screw, I. It isprovided with downward extensions 13 B, which pivotaliy secure it to thestud A. The lower side of the clamp has a hook,K,extendingtherefrom,which is adapted to take into a notch, 0, upon a portion, C,of the drum D C, which is secured by means of a screw, 1), to the studA, and by it rigidly affixed to said stud. The extensions B B straddlethe drum D C, making a very compact arrangement of parts. From theportion D of the drumD C is an extension, E, which is provided with atension-adjusting screw, a, to the end of which is attached a spiralspring, 1), whose other end is secured to the clamp F,or an extensionthereof. \Vhen it is desired to withdraw the brush from the commutator,it is only necessary to draw the clamp F back and put the hook K intothe notch c, the tension of the spring 1) serving to hold the hook insaid notch, so that the clamp and brush will remain retracted until thehook K is raised, when thetension of the spring I) will immediatelythrow it into operative position against the commutator H.

2 sersee Having now fully set forth my invention and stated itsoperation,what I desire to claim and secure by Letters Patent of theUnited States is- 1. A commutatorbrush for a dynamo or othermagneto-electric machine, composed of strips G, diagonally arranged tothe plane of said brush, soldered together at one end, and hearing atthe other end upon the commutator, whereby an increased edgewise andlengthwise bearing of said brush upon the commutator is secured, so thateach strip is snbj eeted to the same amount of wear, and falling away ofthe lowermost strip, causing sparking and short-circuiting of thecurrent, is obviated.

2. A commutator-brush composed of a multiplicity of sheetmetal stripsdiagonally arranged to the plane of said brush, and means for securingsaid strips together at the end remote from the commutator.

3. A commutator-brush composed of a 111111 tiplicity of sheetmetalstrips,as G, diagonally arranged to the plane of said brnsh,and metalpieces, as L M, embracing said strips at one eng, all of whicharesoldered together at said en 4. A commutatorbrush consisting of amultiplicity of thin metal strips diagonally arranged to the plane ofsaid brush, soldered or otherwise fastened together at one end, andhaving a bearing upon the commutator at the free and flexible end, thesaid bearing being the resultant of an end,lengthwise, and diagonalbearing.

5. A commutator-brush composed of metal strips diagonally arranged tothe plane of said brush, substantially as described.

6. A commutator-brush composed of strips diagonally arranged to theplane of said brush, and having the axis of the brush arrangedsubstantially at right angles to the axis of the commutator.

In testimony whereof I have hereunto set my hand and seal,this 13th dayof December, 1886, in the presence of two subscribing witnesses.

osnonn P. LOOMIS. [LS] XVitnesses:

Hownnn L. GALLUPH, ELISA J. OnILsoN.

